Mount
如何在不知道掛載點的情況下判斷設備 UUID 已掛載？
系統：Linux Mint 19.1 Cinnamon 64 位，基於 Ubuntu 18.04 LTS。
我想知道是否可以獲得以下資訊：
這個 UUID （塊設備的）是否已安裝？（不知道掛載點）
儘管如此，我玩了半天，我想不通。
我至少創建了一些工作程式碼，在這些程式碼下面解除安裝並關閉兩個 USB 硬碟驅動器。
我的程式碼的目前臨時版本如下所示：
dismount_and_poweroff_external_drives() { name_external_drive_500gb_ntfs='500GB NTFS USB 2.0 HDD' name_external_drive_2_0tb_ext4='2.0TB Ext4 USB 3.0 HDD' uuid_external_drive_500gb_ntfs='xxxxxxxxxxxxxxxx' # censored uuid_external_drive_2_0tb_ext4='xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx' # censored path_external_drive_500gb_ntfs="/dev/disk/by-uuid/${uuid_external_drive_500gb_ntfs}" path_external_drive_2_0tb_ext4="/dev/disk/by-uuid/${uuid_external_drive_2_0tb_ext4}" tput bold; tput setaf 3; printf '%b' "\\n${name_external_drive_500gb_ntfs} un-mount\\n"; tput sgr0 # info test ‘-b FILE’: True if FILE exists and is a block special device. if [ ! -b "${path_external_drive_500gb_ntfs}" ] then tput bold; tput setaf 4; printf '%b' "The device is not plugged in or powered on.\\n"; tput sgr0 else if umount "${path_external_drive_500gb_ntfs}" then tput bold; tput setaf 2; printf '%b' "Un-mounting OK.\\n"; tput sgr0 if udisksctl power-off --block-device "${path_external_drive_500gb_ntfs}" then tput bold; tput setaf 2; printf '%b' "Powering-off OK.\\n"; tput sgr0 else tput bold; tput setaf 1; printf '%b' "Powering-off Failed.\\n"; tput sgr0 fi else tput bold; tput setaf 1; printf '%b' "Un-mounting Failed.\\n"; tput sgr0 fi fi printf '\n' tput bold; tput setaf 3; printf '%b' "\\n${name_external_drive_2_0tb_ext4} un-mount\\n"; tput sgr0 # info test ‘-b FILE’: True if FILE exists and is a block special device. if [ ! -b "${path_external_drive_2_0tb_ext4}" ] then tput bold; tput setaf 4; printf '%b' "The device is not plugged in or powered on.\\n"; tput sgr0 else if umount "${path_external_drive_2_0tb_ext4}" then tput bold; tput setaf 2; printf '%b' "Un-mounting OK.\\n"; tput sgr0 if udisksctl power-off --block-device "${path_external_drive_2_0tb_ext4}" then tput bold; tput setaf 2; printf '%b' "Powering-off OK.\\n"; tput sgr0 else tput bold; tput setaf 1; printf '%b' "Powering-off Failed.\\n"; tput sgr0 fi else tput bold; tput setaf 1; printf '%b' "Un-mounting Failed.\\n"; tput sgr0 fi fi printf '\n' }我忘了強調接受的解決方案必須是POSIX編寫的。
原始解決方案
UUID=<device_uuid> mount | egrep $(readlink -f /dev/disk/by-uuid/${UUID}) && echo mounted弗拉斯蒂米爾的筆記
- 從幫助中使用
-e代替 ,可能是個好主意：-f``readlink-e, --canonicalize-existing canonicalize by following every symlink in every component of the given name recursively, all components must exist相比於：
-f, --canonicalize canonicalize by following every symlink in every component of the given name recursively; all but the last component must exist據我了解，可以
-e保證整個路徑存在，可能會更好，需要額外的驗證或引用。**不幸的是，該-e選項被發現不符合POSIX標準，所以運氣不好。**將所有資訊留在這里以供將來參考。
- 原始解決方案中沒有雙引號，我建議將它們與一個尾隨空格一起添加作為一種安全措施，以避免匹配例如
sda11或類似的。- 還可以利用POSIX -defined**
fgrep來匹配固定字元串**，或者甚至更好地匹配僅以該設備開頭的行，使用grep "^dev_name".- 正如Mark Plotnick所指出的，
mount它本身可能不是POSIX定義的，再次引用會很方便，但無論如何我已經將程式碼更改為直接讀取/proc/mounts。似是而非的功能
檢查 UUID 是否已掛載的結果函式****可能類似於：
is_uuid_mounted() { readlink_output=$( readlink -f /dev/disk/by-uuid/"${1}" ) [ -n "${readlink_output}" ] && grep -F "${readlink_output} " /proc/mounts > /dev/null 2>&1 }完整的工作腳本
#!/bin/sh set -eu translate_uuid_to_device_name() { # Linux-specific; needs *BSD revision readlink -f -n /dev/disk/by-uuid/"${1}" } is_uuid_mounted() { device_name=$( translate_uuid_to_device_name "${1}" ) if [ -n "${device_name}" ] then # 1. basic regex should be working across platfotms # tested on FreeBSD, OpenBSD, NetBSD with success # I prefer the starting with (^) rather than filtering throung all text # 2. /proc/mounts is not available on all *BSDs, needs revision proc_mounts=$( grep "^${device_name} " /proc/mounts ) [ -n "${proc_mounts}" ] fi } # Simplest Usage Example if is_uuid_mounted "PUT_SOME_UUID_IN_HERE" then echo "This UUID is mounted." else echo "This UUID isn't mounted." fi隨時在評論中解決更多問題。